Dermatology Department, University of Modena and Reggio Emilia, Modena, Italy.
The Kittner Skin Cancer Screening & Research Institute, Sheba Medical Center and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
J Eur Acad Dermatol Venereol. 2019 Dec;33(12):2273-2282. doi: 10.1111/jdv.15784. Epub 2019 Aug 19.
Negative pigment network (NPN) is a dermoscopic structure observed more frequently among melanomas than naevi. Precise tissue correlates of NPN are still elusive.
To describe the reflectance confocal microscopy (RCM) findings underlying NPN in melanocytic neoplasms.
We retrospectively identified all melanocytic neoplasms displaying dermoscopic NPN that were imaged with RCM and subsequently biopsied between 2011 and 2015. Images from study lesions (n = 50) were evaluated for dermoscopic and RCM Criteria. Histopathological correlational study was performed in a subset of cases (n = 15).
The study data set consisted of 21 melanomas (42%) and 29 naevi (58%). Melanomas showed more frequently irregularly shaped globules than naevi (62% vs. 28%, P = 0.03); NPN also tended to be more asymmetrically located among melanomas (86%) than naevi (62%), albeit not significant (P = 0.06). Under RCM, we observed three patterns of dermal papillae (DP): (i) 'Dark DP' - whereby DP were devoid of nests and often surrounded by a junctional proliferation as thick-Rings - this pattern was less common among melanomas (n = 10, 48%) than naevi (n = 23, 79%, P = 0.02); (ii) 'Bulging DP' - whereby junctional nests of melanocytes protrude into the DP, often in association with junctional proliferation as Meshwork - with comparable frequency among melanomas (n = 12, 57%) and naevi (n = 23, 79%, P = 0.09) and (iii) 'Expanded DP' - whereby junctional and/or dermal nests filled and expanded the DP, often in association with dermal-epidermal junction (DEJ) Clod pattern - seen more commonly among melanomas (n = 15, 71%) than naevi (n = 6, 21%, P < 0.001). Dermoscopy-RCM correlation and comparison to histopathological findings show that the hypo-pigmented lines of NPN correlate with broadened epidermal retes, which often show overlying surface dells and wedge-shaped hypergranulosis, while the pigmented globules of NPN correlate with a predominantly-junctiona of melanocytes along and between the elongated retes.
Dermoscopic NPN correlates with three DEJ RCM patterns with differing frequency between naevi and melanomas.
负性色素网络（NPN）是一种在黑素瘤中比痣更常见的皮肤镜结构。NPN 的精确组织学相关性仍难以捉摸。
描述黑素细胞肿瘤中 NPN 的反射共聚焦显微镜（RCM）表现。
我们回顾性地确定了 2011 年至 2015 年间进行 RCM 成像并随后进行活检的所有显示皮肤镜 NPN 的黑素细胞肿瘤。对研究病变的图像（n=50）进行皮肤镜和 RCM 标准评估。在一组病例（n=15）中进行组织病理学相关性研究。
研究数据集包括 21 例黑素瘤（42%）和 29 例痣（58%）。黑素瘤比痣更常显示形状不规则的球状物（62%比 28%，P=0.03）；NPN 也更倾向于在黑素瘤中不对称分布（86%比痣中 62%，尽管无统计学意义（P=0.06）。在 RCM 下，我们观察到三种真皮乳头（DP）模式：（i）“暗 DP”- DP 缺乏巢，通常被作为厚环的交界性增生所环绕-这种模式在黑素瘤中比痣中更常见（n=10，48%比 n=23，79%，P=0.02）；（ii）“隆起 DP”- 此处交界性黑素细胞巢突出到 DP 中，通常与作为网状结构的交界性增生相关-在黑素瘤中（n=12，57%）和痣中（n=23，79%）的频率相当，P=0.09）和（iii）“扩张 DP”- 此处交界性和/或真皮巢充满并扩张 DP，通常与表皮-真皮交界处（DEJ）的块状模式相关-在黑素瘤中更常见（n=15，71%）比痣中（n=6，21%，P<0.001）。皮肤镜-RCM 相关性和与组织病理学发现的比较表明，NPN 的色素减退线与扩大的表皮 rete 相关，rete 上通常有覆盖的表面凹陷和楔形过度角化，而 NPN 的色素球状物与主要沿和在拉长 rete 之间的黑素细胞交界相关。
皮肤镜 NPN 与黑素瘤和痣之间存在三种不同频率的 DEJ RCM 模式相关。
